WHAT ARE GROUNDWATER BANKS?
Groundwater banking is a water management mechanism that helps farmers save excess water that can cause flooding during monsoon season. During the drought season, groundwater banks can allow the stored water to evaporate and provide moisture for the soil. Stored water can also be used for agricultural purposes (depending on the type of groundwater bank).
OPEN-SYSTEM GROUNDWATER BANKS
Open system groundwater banks work on the principle of storing water underground through digging three large ponds deep into the aquifer level, which can allow for water to be absorbed into the groundwater level directly (a process that usually takes a while to occur).
When the rain falls, the groundwater bank would fill water into the aquifer level, allowing the water to spread out between the three ponds. At the same time, the groundwater would automatically overflow into the ponds, increasing the water level, and allowing water to be acquired and used by farmers without the need to dig for water sources. An open system groundwater bank can help save several million bahts for farmers every year.
CLOSED-SYSTEM GROUNDWATER BANKS
Unlike open system groundwater banks that are used to store water, closed system groundwater banks are mainly used to fix the problem of water drainage in farms. Closed system groundwater banks are created by digging holes around 3-5 meters deep (not past the soft clay layer). Concrete or geotextile are then used to reinforce the sides of the hole, a PVC pipe is placed in the middle, and the hole is then filled up with rocks.
Such groundwater banks would help farmers when the excess rainfall during the monsoon season cause problems related to flooding and accumulated wastewater, which does not only impact the farmer's crops but also their health. Even though the “stored” or absorbed water cannot be pumped up directly, a closed system groundwater bank can add moisture to the soil. This will allow more soil moisture during the drought season, as well as higher water levels in ponds near the groundwater banks.